Preparation And Properties Of Diamond Reinforced Polymer Thermal Conductive Composites

The continuous development of microelectronics technology has caused the heat dissipation of electronic components.This problem has become one of the important reasons restricting the integrated development of electronic devices.The thermal interface material can be filled between the heating element and the heat sink.It plays the role of expelling the air in the gap and promoting the thermal conduction of the interface.In this paper,diamond particles are used as thermal conductive fillers.Epoxy resin and silicone rubber are used as substrates.Hot-melt film method and blending method are used to prepare thermal interface materials.By characterizing the thermal conductivity and mechanical properties of samples,the influence of factors such as the filling amount of diamond fillers,the preparation method and the compound filling on the comprehensive performance of the material is studied.In the research of filling single particle size fillers,thermal conductivity of the materials increases firstly and then decreases with the increase in the filling amount of diamond fillers.When the filling amount is 70 wt.%,thermal conductivity reaches the maximum value,which is 1.18 W/(m?K).When the filling amount further increases,thermal conductivity decreases.As the particle size of diamond fillers increases,the overall thermal conductivity of the material shows an upward trend.But it decreases in the range of 5 ?m and 10 ?m.In the research of hot-melt film method,thermal conductivity in the direction of parallel layup is 0.97 W/(m?K)when the filling amount reaches 60 wt.%.It is 24% higher than the sample of the blending method.In the compound filling scheme,when the filling amount of 5 ?m diamond particles is 40 wt.% and 60 ?m fillers is 30 wt.%,the composite material has the largest thermal conductivity of 1.37 W/(m?K).And this is 16% higher than filling single particle fillers.When the filling amount grows higher and the particle size of the fillers is larger,the numerical simulation results and the experimental results of the composite material fit better.The numerical simulation results of hot-melt film method and compound filling composite material are similar to the experimental results.This result verifies the accuracy of the thermal conductivity model.And it proves that hot-melt film method and compound filling method can effectively improve the material's thermal conductivity.